There is a need to improve electrode plates in order to increase the energy density of power storage devices. For example, Patent Literature 1 and Patent Literature 2 each disclose an electrode plate including a bare part formed in part of a core in the width direction (an end portion in the width direction) in order to increase the capacity of a non-aqueous electrolyte secondary battery. The bare part is a part in which the surface of the core is exposed and to which an electrode plate lead is to be connected. Since the active material layer of such an electrode plate has a larger area than the active material layer of an electrode plate having a bare part formed over the full width of a core, such an electrode plate increases the capacity of a battery. The width direction of the electrode plate corresponds to the axial direction of a wound-type electrode body, and the longitudinal direction corresponds to the winding direction of the electrode body.